<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>论文管理系统</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 0;
            background-color: #f4f4f4;
        }
        .container {
            width: 80%;
            margin: 0 auto;
            overflow: hidden;
        }
        header {
            background: #333;
            color: #fff;
            padding-top: 30px;
            min-height: 70px;
            border-bottom: #77b1e5 3px solid;
        }
        header a {
            color: #fff;
            text-decoration: none;
            text-transform: uppercase;
            font-size: 16px;
        }
        header ul {
            padding: 0;
            list-style: none;
        }
        header li {
            display: inline;
            padding: 0 20px 0 20px;
        }
        .banner {
            background: #77b1e5;
            color: #fff;
            text-align: center;
            padding: 100px 0;
        }
        .banner h1 {
            margin: 0;
            font-size: 3em;
            text-transform: uppercase;
        }
        .content {
            background: #fff;
            padding: 20px;
            margin: 20px 0;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
        }
        .content h2 {
            text-align: center;
            margin-bottom: 20px;
        }
        .content p {
            text-align: justify;
            line-height: 1.6;
        }
        .features {
            display: flex;
            justify-content: space-around;
            flex-wrap: wrap;
        }
        .feature {
            background: #e0e0e0;
            padding: 20px;
            margin: 10px;
            border-radius: 5px;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
            width: calc(33% - 40px);
            text-align: center;
        }
        .feature img {
            max-width: 100%;
            height: auto;
        }
        .search-section {
            text-align: center;
            margin: 40px 0;
        }
        .search-section input[type="text"] {
            padding: 10px;
            width: 300px;
            margin-right: 10px;
            border: 1px solid #ccc;
            border-radius: 5px;
        }
        .search-section input[type="submit"] {
            padding: 10px 20px;
            background: #77b1e5;
            color: #fff;
            border: none;
            border-radius: 5px;
            cursor: pointer;
        }
        .search-section input[type="submit"]:hover {
            background: #558ed5;
        }
        footer {
            background: #333;
            color: #fff;
            text-align: center;
            padding: 10px 0;
            margin-top: 20px;
        }
    </style>
</head>
<body>
<header>
    <div class="container">
        <h1>论文管理系统</h1>
        <nav>
            <ul>
                <li><a href="#">首页</a></li>
                <li><a href="#">关于我们</a></li>
                <li><a href="#">联系我们</a></li>
            </ul>
        </nav>
    </div>
</header>

<section class="banner">
    <div class="container">
        <h1>欢迎来到论文管理系统</h1>
    </div>
</section>

<section class="content">
    <div class="container">
        <h2>基本介绍</h2>
        <p>论文管理系统是一个用于管理学术论文的平台，旨在帮助研究人员、学生和教师更有效地组织和查找论文资源。</p>
    </div>
</section>

<section class="content">
    <div class="container">
        <h2>功能介绍</h2>
        <div class="features">
            <div class="feature">
                <img src="https://via.placeholder.com/150" alt="功能图标">
                <h3>论文上传</h3>
                <p>用户可以上传自己的论文，方便日后查找和分享。</p>
            </div>
            <div class="feature">
                <img src="https://via.placeholder.com/150" alt="功能图标">
                <h3>论文搜索</h3>
                <p>强大的搜索功能，帮助用户快速找到所需的论文。</p>
            </div>
            <div class="feature">
                <img src="https://via.placeholder.com/150" alt="功能图标">
                <h3>论文分类</h3>
                <p>论文按学科分类，便于用户浏览和筛选。</p>
            </div>
        </div>
    </div>
</section>

<section class="search-section">
    <div class="container">
        <form action="#" method="post">
            <input type="text" name="search" placeholder="搜索论文...">
            <input type="submit" value="搜索">
        </form>
    </div>
</section>

<footer>
    <div class="container">
        <p>&copy;论文管理系统</p>
    </div>
</footer>
</body>
</html>